Kinetics of pressing of paper web in shoe-type press

Abstract

Проаналізовано конструкції башмачних пресів. Запропоновано принципово нову конструкцію. Розроблено математичну модель пресування паперового полотна на башмачному пресі з новими умовам однозначності, що дає можливість розрахувати кількість видаленої вологи та сухість полотна після пресування.Now forging parts papermaking machines uses many different designs presses. Regardless of the type of construction, the water is filtered through paper to canvas cloth in the transverse direction, filtering water from the cloth can occur in the longitudinal direction (simple presses) or in the transverse direction (shaft with blind holes, grooved shaft, suction shaft). Presses of the native papermaking machines provide a dry cloth when pressed, about 35…40 %. That is not enough, as for drying the paper spent a huge amount of thermal energy in the form of steam, so the development of the press, providing a significant increase in dry is relevant. One way of increasing dryness is usage of shoe press, which by increasing the length of the contact area increased while pressing, so dry cloth before drying section increasing to 50…55 %. Work of presses of papermaking machine is measured by the amount of water removed, and uniform moisture content across the width of fabric after the presses. Dehydration capacity of presses depends primarily on the length of the extrusion zone delighted shaft and on the number of these zones. When pressing simultaneously with dehydration of the paper web changing its structure, increases the contact area between the fibers and the coupling strength between them. In the existing literature does not sufficiently covered shoe-type presses calculation that does not allow constructing them because kinetic regularities of the process is unknown. The purpose of this article is to establish the kinetics of the compaction and main parameters shoe-type press needed to develop methods of calculation and design shoe presses. In the conventional two-shaft presses created considerable common pressure gradient and significantly lower hydraulic pressure gradient. In the developed design will increase the hydraulic pressure gradient by summing the camera of the shoe-type heated compressed air. Under the influence of the total pressure break down the cell structure of the paper web from which water is removed that the action of hydraulic pressure filtered in cloth, from cloth in the grooves of the shaft. This article consists of 5 items: problem, purpose of, the physical model of the process, the mathematical model of the process and conclusions. Each item clearly defines the essence of the article